The subject matter described herein relates generally to methods and systems for assembling a wind turbine including a pitch system, and more particularly, to systems and methods for assembling a pitch assembly for use in a wind turbine.
At least some known wind turbines include a tower and a nacelle mounted on the tower. A rotor is rotatably mounted to the nacelle and is coupled to a generator by a shaft. A plurality of blades extend from the rotor. The blades are oriented such that wind passing over the blades turns the rotor and rotates the shaft, thereby driving the generator to generate electricity.
Because many known wind turbines provide electrical power to utility grids, at least some wind turbines have larger components (e.g., rotors in excess of thirty-meters in diameter) that facilitate supplying greater quantities of electrical power. However, the larger components are often subjected to increased loads (e.g., asymmetric loads) that result from wind shears, yaw misalignment, and/or turbulence, and the increased loads have been known to contribute to significant fatigue cycles on the rotor blades and/or other components of the wind turbine.
At least some known wind turbines include a rotor blade pitch system for use in positioning the rotor blade about a pitch axis to control the speed of the rotor. At least some known wind turbines include a wind turbine control system for controlling the operations of the wind turbine, including the pitch system. In addition, at least some known wind turbines require power to operate the wind turbine control system and the pitch system. During an event of power loss and/or malfunction of the wind turbine control systems, pitch systems may not be able to operate. The power loss event may include power grid loss and/or malfunctioning of the turbine electrical system. Malfunctioning of the wind turbine control system includes failure of a wind turbine control device electrical system, a wind turbine control device communication system, and/or a mechanical system. The power loss event may lead to turbine blade overspeed during which the wind turbine control system may not be available to operate the pitch system.
Accordingly, it is desirable to provide a method and/or apparatus capable of operating the pitch system during periods of electrical power loss and/or wind turbine control system malfunction.